Three masked militants of Izzedin al Qassam, the armed wing of Hamas, told reporters in a news conference held in Jabalya refugee camp in northern Gaza that "we are developing new al Qassam rockets, and it would be a surprise for the (Israeli) enemy."
Current al Qassam rockets have a range of 14 kilometers (8.7 miles), said the group.
"Firing al Qassam rockets at Israel would be escalated and would turn the Days of Penitence (the name of Israel's current operation in Gaza) on (Israeli Prime Minister) Ariel Sharon," said one of the militants.
"Al Qassam Brigades would continue launching al Qassam rockets. Nothing would stop it, neither a security separation wall nor radar. Rockets would hit the depth of Sderot and many other areas," said another militant.